ESLint has a very lightweight development environment that makes updating code fast and easy. If you’ve checked out the code already, then the next step is to make sure you have all of the required utilities. Node.js and npm are the two things you’ll need.
Go to http://nodejs.org to download and install the latest stable version for your operating system.
Most of the installers come with npm already installed, but if for some reason it doesn’t work on your system, you can install it manually using the instructions on the website.
To run ESLint is dev mode you will need to first uninstall the real ESLint utility (if you had previously installed it from npm):
npm remove -g eslint
Next, go to the directory in which you’ve checked out the ESLint source code and run:
npm link
The global eslint will now point to the files in your development repository instead of a globally-installed version from npm. You can now use eslint directly to test your changes.
If you ever update from the central repository and there are errors, it might be because you are missing some dependencies. If that happens, just run npm link again to get the latest dependencies.
ESLint has only one real build script you need to know about: npm test. By running npm test, you are verifying that all JSON files are free of syntax errors, running all tests, and checking the code coverage on those tests.
Be sure to run npm test whenever you make changes to ensure that you’ve not broken anything that was previously working.
Whenever you make changes to the ESLint source files, you’ll need to run npm test to rerun the tests. The workflow is:
npm test to run tests on the command lineYou’ll have to do this each time you make a change. The tests are run automatically whenever a pull request is received, so make sure to verify your changes work before submitting them.